A major strength of this proposal is the blending of the complementary expertise of the two labs in breast and colorectal cancer with a shared interest in exosomes, enabling the formation of a true partnership to establish a clinically applicable method to measure selected proteins in exosomes from the serum of cancer patients. We anticipate that the reliable detection and precise quantification of selected proteins in serum exosomes may enable the eariier diagnosis of patients with breast and colorectal cancer. However, the pilot project will establish normal standards for serum exosomes in normal individuals, and then, initially, compare these results to patients with early and advanced colorectal cancer and advanced breast cancer. As the work progresses, analysis of serum exosomes may prove to have prognostic and predictive value in the management of patients with cancer [1].